public static async Task DeleteContainerIfExists(string containerName)
{
var tcs = new TaskCompletionSource <bool>();
using (await ContainerProvider.Lock.WaitAsync().ConfigureAwait(continueOnCapturedContext: false))
{
if (ContainerProvider.ExecutionStates[containerName] == ContainerExecutionState.Ready)
{
ContainerProvider.ExecutionStates[containerName] = ContainerExecutionState.Deleted;
tcs.SetResult(result: true);
}
else if (ContainerProvider.ExecutionStates[containerName] == ContainerExecutionState.Deleted)
{
return;
}
else
{
ContainerProvider.DeletionTasks[containerName] = tcs;
}
}
await tcs.Task.ConfigureAwait(continueOnCapturedContext : false);
await ContainerProvider
.DeleteContainer(containerName : containerName)
.ConfigureAwait(continueOnCapturedContext: false);
}
public static async Task <bool> CreateContainerIfNotExists(string containerName, string functionId, int memorySize)
{
using (await ContainerProvider.Lock.WaitAsync().ConfigureAwait(continueOnCapturedContext: false))
{
if (ContainerProvider.ExecutionStates.ContainsKey(containerName))
{
return(false);
}
ContainerProvider.ExecutionStates[containerName] = ContainerExecutionState.Creating;
}
var container = await Container
.Create(
name : containerName,
functionId : functionId,
memorySize : memorySize)
.ConfigureAwait(continueOnCapturedContext: false);
await MemoryProvider
.AdjustReservation(
containerName : containerName,
memorySize : memorySize)
.ConfigureAwait(continueOnCapturedContext: false);
ContainerProvider.Containers[containerName] = container;
ContainerProvider.ExpirationTasks[containerName] = ContainerProvider.ExpireContainer(containerName: containerName);
ContainerProvider.QueueWatchTasks[containerName] = ContainerProvider.WatchFunctionExistence(
functionId: functionId,
containerName: containerName);
using (await ContainerProvider.Lock.WaitAsync().ConfigureAwait(continueOnCapturedContext: false))
{
if (ContainerProvider.DeletionTasks.ContainsKey(containerName))
{
ContainerProvider.DeletionTasks[containerName].SetResult(result: true);
ContainerProvider.ExecutionStates[containerName] = ContainerExecutionState.Deleted;
}
else
{
ContainerProvider.ExecutionStates[containerName] = ContainerExecutionState.Ready;
}
}
return(true);
}
private static async Task WatchFunctionExistence(string functionId, string containerName)
{
while (true)
{
var exists = await FunctionsProvider
.Exists(functionId : functionId)
.ConfigureAwait(continueOnCapturedContext: false);
if (!exists)
{
await ContainerProvider
.DeleteContainerIfExists(containerName : containerName)
.ConfigureAwait(continueOnCapturedContext: false);
}
await Task
.Delay(delay : TimeSpan.FromSeconds(15))
.ConfigureAwait(continueOnCapturedContext: false);
}
}
private static async Task ExpireContainer(string containerName)
{
while (true)
{
var timeSinceLastExecution = DateTime.UtcNow - ContainerProvider.Containers[containerName].LastExecutionTime;
var expirationTimeSpan = TimeSpan.FromMinutes(ServerlessConfiguration.ContainerLifeInMinutes);
if (timeSinceLastExecution >= expirationTimeSpan)
{
var delete = false;
using (await ContainerProvider.Lock.WaitAsync().ConfigureAwait(continueOnCapturedContext: false))
{
if (ContainerProvider.ExecutionStates[containerName] == ContainerExecutionState.Ready)
{
ContainerProvider.ExecutionStates[containerName] = ContainerExecutionState.Deleted;
delete = true;
}
else if (ContainerProvider.ExecutionStates[containerName] == ContainerExecutionState.Deleted)
{
return;
}
}
if (delete)
{
await ContainerProvider
.DeleteContainer(containerName : containerName)
.ConfigureAwait(continueOnCapturedContext: false);
return;
}
}
await Task
.Delay(delay : expirationTimeSpan - timeSinceLastExecution)
.ConfigureAwait(continueOnCapturedContext: false);
}
}